1. Field of the Invention
This invention pertains to a winding device to simultaneously wind several widths of material, in particular photopolymer films, onto reel cores, having at least one driven axle on which the reel cores are rotatably arranged, and having a torque-transmission device to transmit a torque from the reel axle to the reel cores, and which has a sliding hub element on the reel axle and a core-receiving element which slides in the reel core and which can be affixed in the latter in the rotating and axial directions.
2. Description of Related Art
Longitudinal cutting machines unwind a width of material from a wide roll and cut it longitudinally into numerous parallel strips of material. At the same time the strips of material thus formed are wound onto reel cores. The individual reel cores can be arranged at intervals on a reel axle. As a rule, there are two reel axles, on which the individual reel cores are arranged staggered with respect to each other. It has proven practical not to drive the individual reel cores at identical rotation speeds. Consequently, the winding tension in each reel can adjust itself independent of the other reels, thus only being influenced by the torque driving that particular reel.
In a prior art device of this type, hub elements, core-receiving elements and spacing tubes are arranged alternately on the reel axle. The core-receiving elements and the spacing tubes can move freely on the reel axle, whereas the hub elements are rigidly attached to the reel axle, although they can be slid axially on bearings. The hub elements have a friction surface which rubs against the friction surface of the matching core-receiving element. The pressure necessary comes from a spring which is installed at one end of the shaft and which exerts pressure on all of the hub elements, core-receiving elements and spacing tubes on one reel axle between itself and a rigid support on the opposite end of the reel axle, which is in the form of a shaft. The magnitude of the transmitted torque is determined by the force exerted by the spring. In this process, the same torque is transmitted to all of the reels. Consequently, all strips of material must have the same width. Otherwise, the winding tension for a narrower strip would be greater than for a wider strip.
The rubbing of the friction surfaces against each other creates a fine dust, which makes it practically impossible to operate the prior art winding device under clean-room conditions without taking additional complex measures. However, clean-room conditions are indispensable, for example, in the manufacture of photopolymer films. Moreover, a change in the cutting program, that is, changing the width of the individual strips of material that are to be wound up, is extremely complicated. The reel axle has to be completely cleared and then retooled in order to ensure that the core-receiving elements, the hub elements and the spacing tubes are in the right position for transmission of the friction force and that a reel core is not coincidentially positioned on a spacing tube.
The object of the present invention is to provide a winding device which can be operated under clean-room conditions and which makes it possible to easily change the cutting program. This task is solved by a winding device of the type described above in that the torque-transmission device is arranged in the radial direction between the reel axle and the reel core, in that the hub element can be affixed in the axial direction on the reel axle, and in that one of the two parts has a device which serves to transmit a torque to the other part while maintaining clean-room conditions.